1. Field of the invention
The present invention relates generally to a slide fastener and more particularly to a separable bottom stop for a concealed type slide fastener.
2. Description of the Prior Art
A typical separable bottom stop of the type described is disclosed in Japanese Utility Model Publication No. 38-7939. The disclosed separable bottom stop comprises a socket box mounted on the lower end of one stringer of the slide fastener, a socket pin integrally formed with the socket box and an insert pin mounted on the lower end of the other stringer. When a slider descends to the separable bottom stop, the insert pin is inserted through the slider into the socket box, thereby uniting the lower ends of both stringers.
Another separable end stop for the concealed type slide fastener is disclosed in Japanese Utility Model Publication No. 51-4816. This conventional separable bottom stop also comprises a socket box mounted on the lower end of one stringer of the slide fastener a socket pin integrally formed with the socket box and an insert pin mounted on the lower end of the other stringer. In addition, the socket box includes respective upper extensions extending upward from the rear surface and one side surface in such a way to surround the socket pin, to thus define with the socket pin a guide corner groove, into which the lower part of the slider fits when the slider descends to the separable bottom stop.
However, these conventional separable bottom stops have the following drawbacks.
Each of the conventional separable bottom stops has its socket box and socket pin formed integrally. The socket box and the socket pin in one integral part must be mounted on the concealed type fastener stringer before the concealed slide fastener is sewn to an article, such as clothes. This is obstructive to the sewing operation. When sewing the concealed type slide fastener to an article, such as clothes, a sewer must seam to the edge of the clothes each narrow folded edge of the fastener stringer. The narrow folded edge of the fastener stringer has at the lower end the socket box which constitutes a taxing bar to the sewing operation.
Furthermore, although two opposed fastener element rows are firmly coupled with each other almost throughout the length of the slide fastener, the socket pin and the upper portion of the insert pin sticking from the socket box only touches each other in a region between the lowermost end of the fastener element rows and the upper end of the socket box. Consequently, the fastener stringers are prone to be accidentally spread apart from this region.
In order to prevent the accidental fracture, the insert pin must be stably fitted in the socket box. For this purpose, the insert pin must be inserted into the socket box deep and so the socket box must be made long. However, this results in another disadvantage that it is difficult to insert the insert pin through the slider into the long socket box.